Construction laborers perform work on the chamber floor concrete infill and wall-facing rebar and formwork for the Charleroi Lock Construction Project at the Monongahela River Locks and Dam 4 in Charleroi, Pennsylvania, March 21, 2023. The U.S. Army Corps of Engineers Pittsburgh District operates the facility and has overseen the construction project at Charleroi to improve inland navigation in the region. The newly constructed chamber is scheduled to fill with water before the summer, and it is planned to go into full operation in 2024. Construction at Charleroi began in 2004. Once finished, the Charleroi project will cost approximately $1 billion, completed over a span of 20 years. Once complete, the Pittsburgh District will begin removing the river dam at Elizabeth, Pennsylvania, to create one continuous navigable pool between Charleroi and Braddock, Pennsylvania. (U.S. Army Corps of Engineers Pittsburgh District photo by Michel Sauret)